Messing around with sorting arrays

sort.js

// ---------- Messing around with sorting --------------
(function stableSort(v) {
    var dv = [];
    
    for (var i=0; i<v.length; i++) {
        dv[i] = [v[i], i];
    }

    dv.sort();

    for (var i=0; i<v.length; i++) {
        v[i] = dv[i][0];
    }

    console.log('attempt 1: ', dv);

}([35, 6, 236, 7, 8, 324, 5, 1 , 3]));

// ------------------------
(function (arr) {
    console.log('attempt 2: ', arr.sort());
}([35, 6, 236, 7, 8, 324, 5, 1 , 3]));

// ------------------------
(function(array) {
    array.sort(function (a, b) {
        return a-b;
    });
    console.log('attempt 3: ', array); 
}([35, 6, 236, 7, 8, 324, 5, 1 , 3]));

// ------------------------
(function(array) {
    array.sort();
    console.log('attempt 4: ', array); 
}(['tyrone', 'joe', 'alex', 'vinny', 'rob', 'zack', 'andy', 'eric' , 'darren']));

// ------------------------
(function(array) {
    var objectArray = [
        {firstname: 'Marie',    lastname: 'Doe',    age: 28},
        {firstname: 'Will',     lastname: 'Brown',  age: 28},
        {firstname: 'James',    lastname: 'White',  age: 28},
        {firstname: 'John',     lastname: 'Doe',    age: 25},
        {firstname: 'Sarah',    lastname: 'Doe',    age: 25},
        {firstname: 'George',   lastname: 'Williams',   age: 25}
    ];

    objectArray.sort(function callbackFunc(a,b){
        if(a.lastname === b.lastname){
            if(a.firstname === b.firstname){
                return 0;
            }
            return (a.firstname < b.firstname) ? -1 : 1;
        }
        return (a.lastname < b.lastname) ? -1 : 1;
    });

    console.log('attempt 5: ', objectArray);
}());